Coil developing apparatus

ABSTRACT

Apparatus for developing one or more coil groups of electrically conductive wire. The apparatus includes a coil turn-forming assembly having a jump form portion and a snap-out form portion. The jump form portion includes a plurality of turn-gauging steps with an interruption formed at one side. The snap-out form portion is supported adjacent to the interruptions on the turngauging steps and includes a corresponding number of snap-out winding form plates, each having a fill-in winding section for spanning one of the associated interruptions on the jump form portion. The apparatus also includes a flyer for placing wire on the coil turn-forming assembly to generate turns and a jump means for locating a turn-gauging step of the jump form portion in the path of the wire being wound by the flyer. Concurrently as the jump means locates a turn-gauging step in the path of the wire wound by the flyer, a snap-out plate is extended to place a fill-in winding section in alignment with its associated interruption of a turn-gauging step. The turn-gauging step of the jump form portion and its associated fill-in winding section cooperate to provide a form for winding or generating turns of a predetermined length for receipt in a coil group accommodating means or device. Preferably, the coil group accommodating means is comprised of spaced curved blades defining turn receiving slots. The spaced curved blades and corresponding fill-in winding sections of the snap-out plates have associated mating curved surfaces whereby, when a snap-out plate is engaged with a curved blade, the entry of the turns of a coil being generated into the corresponding turn receiving slot is facilitated by the mating curved surfaces. Thus each coil is developed directly in the coil group accommodating means as the turns for the coil are generated about the coil turn-forming assembly. Also, the jump form portion and the snap-out plates may be supported for movement in essentially a vertical direction, and the curved blades are supported in alignment with the snap-out plates so that force of gravity facilitates the removal of the turns from the coil form assembly. Additionally at least part of the jump form portion is movable relative to the snap-out portion during the turn-generating operation for selectively varying the lengths of successive turns. A coil group is developed in the coil group accommodating means by producing a plurality of serially connected wound coils of a coil group in the coil group accommodating means. Thereafter the coil group may be inserted directly from the coil group accommodating means into preselected slots of a stator core.

United States atent Arnold June 27, 1972 [54] COIL DEVELOPING APPARATUS[72] Inventor: Richard B. Arnold, Fort Wayne, Ind.

[73] Assignee: General Electric Company [22] Filed: June 1, 1970 [21]Appl. No.: 42,150

Related U.S. Application Data [60] Division of Ser. No. 884,145, Dec.11, 1969, Pat. No. 3,579,791, which is a continuation-in-part of Ser.No. 748,406, July 29, 1968, abandoned.

[52] U.S. Cl. ..29/205 R, 29/596, 140/92.1, 242/7.09, 242/82 [51] Int.Cl. ..H02k 15/00 [58] Field of Search ..29/596, 598, 205 R, 205 D;140/921; 242/7.09, 82

[56] References Cited UNITED STATES PATENTS 3,522,650 8/1970 Cutler etal ..29/596 1,396,033 11/1921 Francis ..l40/92.1

Primary ExaminerJ ohn F. Campbell Assistant Examiner-Carl E. HallAttorney-John M. Stoudt, Radford M. Reams, Ralph E. Krisher, Jr., OscarB. Waddell, Jr. and Frank L. Neuhauser [57] ABSTRACT Apparatus fordeveloping one or more coil groups of electrically conductive wire. Theapparatus includes a coil tumforrning assembly having a jump formportion and a snap-out form portion. The jump form portion includes aplurality of turn-gauging steps with an interruption formed at one side.The snap-out form portion is supported adjacent to the interruptions onthe tum-gauging steps and includes a corresponding number of snap-outwinding form plates, each having a fill-in winding section for spanningone ofthe associatedinterruptions on the jump form portion.

The apparatus also includes a flyer for placing wire on the coiltum-forming assembly to generate turns and a jump means for locating aturn-gauging step of the jump form portion in the path of the wire beingwound by the flyer. Concurrently as the jump means locates a tum-gaugingstep in the path of the wire wound by the flyer, a snap-out plate isextended to place a fillin winding section in alignment with itsassociated interruption of a tum-gauging step. The tum-gauging step ofthe jump form portion and its associated fill-in winding sectioncooperate to provide a form for winding or generating turns of apredetermined length for receipt in a coil group accommodating means ordevice. Preferably, the coil group accommodating means is comprised ofspaced curved blades defining turn receiving slots. The spaced curvedblades and corresponding fill-in winding sections of the snap-out plateshave associated mating curved surfaces whereby, when a snap-out plate isengaged with a curved blade, the entry of the turns of a coil beinggenerated into the corresponding turn receiving slot is facilitated bythe mating curved surfaces. Thus each coil is developed directly in thecoil group accommodating means as the turns for the coil are generatedabout the coil turn-forming assembly. Also, the jump form portion andthe snap-out plates may be supported for movement in essentially avertical direction, and the curved blades are supported in alignmentwith the snap-out plates so that force of gravity facilitates theremoval of the turns from the coil form assembly.

Additionally at least part of the jump form portion is movable relativeto the snap-out portion during the turn-generating operation forselectively varying the lengths of successive turns.

A coil group is developed in the coil group accommodating means byproducing a plurality of serially connected wound coils of a coil groupin the 001i group accommodating means.

Thereafter the coil group may be inserted directly from the coil groupaccommodating means into preselected slots of a stator core.

10 Claims, 15 Drawing Figures PATENTEDJUMYIQIZ 3.672.027

- SHEET 6 or 6 INVENTOR. FP/Char'd BAr'no/a',

BYWM/ COIL DEVELOHNG APPARATUS CROSS-REFERENCE TO RELATED APPLICATIONSThis application is a division of my co-pending applicau'on Ser. No.884,145, filed on Dec. 11, 1969, now US. Pat. No. 3,579,791; whichapplication is a continuation-impart of my application, Ser. No.748,406, filed July 29, 1968, now abandoned.

BACKGROUND OF THE INVENTION This invention relates generally toapparatus for developing wound coils for use in electromagnetic devices.More particularly, the invention relates toapparatus for developingcoils of electrically conductive wire for use in a stator member of adynamoelectric machine such as a motor.

conventionally, the coils for a particular coil group of the stator of adynamoelectric machine, such as a motor, are wound on a collapsiblearbor type of windingv machine. In this kind of machine, after coils forthe particular coil group have been wound on the arbor, the arbor iscollapsed into a smaller cross-sectional configuration to permit removalof the coils from the winding machine. The coils are removed by hand,taped or clipped and in one approach are subsequently inserted by handinto a coil group accommodating means or device such as a coil injectionmachine or tooling, which in turn, insert the coils into the desiredslots of an electromagnetic device such as a stator. Although machineshave been proposed for mechanically transferring the windings from coilwinding equipment to coil injection tooling, the combined operations arestill time consuming, costly and have not achieved the desired level ofproduction efficiency.

There is a need therefore for a coil developing apparatus wherein thecoils of a coil group can be developed in the coil injection tooling, orother coil group accommodating device such as a transfer mechanismwithout requiring a collapsible arbor. Also, it is particularlydesirable that such an apparatus be readily adapted for use with anindexing turntable arbor or other conveyor such as an in-line type ofproduction operation.

Accordingly, it is a general object of my invention to provide animproved apparatus for developing coils for use in an electromagneticdevice.

A more specific object of the present invention is to provide animproved apparatus for developing at least one coil group directly intoa coil injection tooling or other coil group accommodating device thatdoes not require a collapsible arbor.

It is still another object of the present invention to provide animproved apparatus for developing at least one coil directly into coilinjection tooling or other coil group accommodating device, whichapparatus may selectively vary the lengths of successive turns of thecoil.

A further object of my invention is to provide an improved apparatus fordeveloping a coil group for a dynamoelectric machine, such as anelectric motor, that is readily adapted for use in a turntable or otherconveyor means, such as in an inline type of production operation.

SUMMARY OF THE INVENTION In accordance with one form of my invention, Ihave provided an apparatus for developing a coil group of electricallyconductive wire which includes a non-collapsible coil tumforrningassembly having a. jump form portion and a snap out form portion. Thejump form portion is formed with-a plurality of turn-gauging steps, andthe snap-out form portion has a plurality of snap-out winding form platswith fill-in winding sections corresponding to the turn-gauging steps ofthe jump form portion. Further, the apparatus includes a winding meansfor generating turns of wire about the coil tum-forming assembly. A coilgroup accommodating means or device is supported adjacent to thesnap-out form portion of the coil turn-forming assembly. Means areprovided for successively locating the tumgauging steps of the jump formportion in the path of the wire being placed by the winding means andfor successively releasing the snap-out winding form plates to positioncorresponding fill-in winding sections in engagement with the coil groupaccommodating means and in the path of the wire generating the turns.Thus one of the tum-gauging steps of the jump form portion and one ofthe fill-in winding sections of the snap-out plates cooperate to providea form for generating turns of a predetermined length for one coil ofthe coil group.

According to a more specific aspect of the invention, at least one ofthe snap-out winding form plates is spring-biased to an extendedposition and latched in a retracted position. Also, a means is includedfor releasing the snap-out winding form plate from its latched positionas a corresponding turngauging step of the jump form portion is locatedin the path of the wire being wound by a winding means such as a flyer.Preferably, the coil group accommodating mean includes a plurality ofspaced curved blades that define turn receiving slots. The curved bladesare supported in an essentially vertical position, and one of thesnap-out winding form plates when in the extended position engages oneof the curved blades to complete a tum-gauging step in the path of thewire for generating turns of a predetermined length and for guidingthese turns into the turn receiving slots of the coil groupaccommodating means during the turn-generating operation. Thus the coilis formed directly in the coil group accommodating means. The jump fon'nportion and the snap-out winding form plates are also preferablysupported for movement in an essentially vertical direction, and thecurved blades of the coil group accommodating means are supported inalignment with the snap-out winding form plates whereby the force ofgravity facilitates the removal of turns from the coil form assemblywhen one of the snap-out plates engages its associated curved blade.Also at least part of the jump form portion is movable relative to thesnap-out form portion during the tum-generating operation forselectively varying the lengths of successive turns.

One important advantage of the present invention is that it is possibleto develop the coils of two or more coil groups efiiciently in a coilgroup accommodating means, such as coil injection tooling, using onlyone coil tum-forming assembly, and then efiectively insert the coilgroups directly from coil group accommodating means into the slots of astator core or other slotted structure. Thus, savings in labor,equipment, costs, and time are readily obtained with the presentinvention as well as a reduction in the tendency of the turns tocross-over one another as the coils are being developed into the slotsof the slotted structure.

Another advantage of the improved arrangement is that the coil groupaccommodating means can be readily positioned with respect to the coiltum-forming assembly by a simple horizontal movement, as for example, byindexing a turntable or moving the coil group accommodating means on aconveyor or other means.

The subject matter which I regard as my invention is particularlypointed out and distinctly claimed in the concluding portion of thespecification. The invention itself, however, together with furtherobjects and advantages thereof, may be best understood by reference tothe following description taken in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings,

FIG. 1 is a side elevational view of the winding head and coil groupaccommodating means of the coil developing apparatus embodying one formof my invention and illustrating the noncollapsible coil tum-formingassembly in the initial position for winding a first coil into the coilgroup accommodating means;

FIG. 2 is a view corresponding to the view shown in FIG. 1 wherein thecoil tum-forming assembly is shown with a second turn-gauging step inthe path of the wire being wound by the flyer;

FIG. 3 is an enlarged perspective view of the wire cut-off and holdingdevice shown in the hold position;

IOIO42 0024 FIG. 4 is an enlarged fragmentary view shown in perspectivecorresponding to the view shown in FIG. 3 wherein the wire cut-off andholding device is shown in the open position;

FIG. 5 is an enlarged side elevational view corresponding to the viewsshown in FIGS. 1 and 2, partially sectionalized to show the variousparts thereof;

FIG. 6 is a bottom plan view of the coil tum-forming assembly shown inFIG. 5 without any sectionalization of the parts and without the coilgroup accommodating means being shown;

FIG. 7 is a view in perspective of the snap-out form portion of the coiltum-forming assembly;

FIG. 8 is a partial sectional view through one of the snap-out windingform plates and through a portion of the snap-out form portion housing,illustrating the latch pawl mechanism of the snap-out winding formplates;

FIG. 9 is a view in perspective of a snap-out plate with the latch pawlmechanism shown in an exploded view;

FIG. 10 is a view in perspective of the mid-form section of the coiltum-forming assembly and the stripper;

FIG. 11 is a simplified schematic diagram in perspective of the driveand control assembly;

FIG. 12 is a sectional view of the jump arm assembly illustrating howtranslational movement is imparted to the jump tube;

FIG. 13 is a view in perspective of a machine wherein the improvedapparatus is mounted on a turntable to illustrate how the coil groupaccommodating means with the coil groups wound thereon can be indexed toa coil injecting station where the coil groups are axially inserteddirectly from the coil group accommodating means into the slots of astator core;

FIG. 14 is an enlarged side elevational view similar to FIG. 5, butillustrating a coil turn-forming assembly incorporating anotherembodiment of the invention in which the back-form section is movablerelative to the snap-out winding form portion during turn generation;and

FIG. 15 is a bottom plan view of the coil turn-fonning assembly shown inFIG. 14 without any sectionalization of the parts and without the coilgroup accommodating means being shown.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Having more specific referencenow to FIGS. 1 through 10, I will now describe the improved coildeveloping apparatus 18 and more specifically the winding head 19 shownin FIGS. 1 and 2 with a preferred coil group accommodating means ordevice in the form of coil injection tooling 20 in position under thewinding head 19.

The winding head 19 includes a non-collapsible coil tumforming assembly21, winding means in the form of a flyer 22, a wire cutter and holder 23and a stripper 24. In this illustrated embodiment of the invention, thewinding head 19 is adapted to generate the turns for a coil groupcomprising up to five serially connected coils of electricallyconductive wire. Each coil may be one or more turns of wire and normallywill be several such turns. The coils, as will hereinafter be more fullyexplained, are formed in the coil group accommodating means 20 as theindividual turns are generated on the coil tum-forming assembly 21. Asthe individual turns are generated, they are stipped off the coiltum-forming assembly 21 essentially by the last wound turns forcing thepreviously wound turns downwardly into one of the five turn receivingslots 25, 26, 27, 28 and 29 (see FIG. 5) of the coil group accommodatingdevice 20. Also, the stripping of the turns is aided by the force ofgravity. The coil receiving slots 25, 26, 27, 28 and 29 are defined byspaced curved blades 30, 31, 32, 33 and 34. A more detailed descriptionof one coil group accommodating device that may be used in conjunctionwith the winding head 19 is presented in my co-pending application, Ser.No. 875,895 assigned to the same assignee as the present application andhaving an effective filing date the same day as the original parentapplication, Ser. No. 748,406 of the present application.

Coil turn-forming assembly 21 includes a jump form portion 35, with amid-form section 36 and a back-form section 37, and a snap-out formportion 38. As is best seen in FIG. 5, the snap-out portion 38 includesa plurality of guides or guide means in the form of snap-out windingform plates 39, 40, 41, 42 and 43 which are biased to extended positions(downwardly in FIG. 7) by springs 44, 45, 46, 47 and 48. The back-formsection 37 and the mid-form section 36 are supported on a jump plate 50attached to a jump tube 51. The back-form section 37 is adjustablymounted in two elongated slots 52, 53 (see FIG. 6) of the jump plate 50so that the backform section 37 can be moved relative to the mid-formsection 36 to allow the coil turn lengths to be adjusted by increasingor decreasing the spacing between the turn-gauging steps 54, 55, 56, 57and 58 on the back-form section 37 and mid-form section 36. In order topermit the back-fonn section 37 to accommodate relatively short turnlengths, the back-form section 37 is provided with an opening 59 so thatit can pass over the stripper 24 and stripper actuating shaft 60.

In this exemplification of the invention, the mid-fonn section 36 andback-form section 37 define five tum-gauging steps 54, 55, 56, 57 and 58which are interrupted at the side of the mid-form section 36 adjacent tothe snap-out form portion 38. The tum-gauging steps 54, 55, 56, 57 and58 are arranged so that the turns for the coil with turns of shortestlength are generated initially and turns for coils having greater turnlengths are then successively generated. It will be seen in FIG. 5, thateach of the tum-gauging steps 54,55, 56, 57 and 58 are formed with anadjacent bevel 61 that is approximately 45 in the exemplification of myinvention. Also, it will be noted that each of the tum-gauging steps ispitched at a slight angle, preferably in the order of 3 on the mid-formsection, to facilitate the downward movement of the turns. The flyer 22is aligned so that the wire 62 fed by the flyer 22 will strike the bevel61 of the steps thereby effecting a downward movement that will cause aforce to be exerted against any turns previously wound. In this mannerthe turns are effectively pushed downwardly into the coil receivingslots 25, 26, 27, 28 and 29 of the coil injection tooling 20 or othercoil receiving or coil group accommodating device, to develop the coilsin the slots. Also, because of the vertical disposition of the steps,the removal of turns from the steps is aided by the force of gravitywithout need for collapsing any of the winding form components.

The mid-form section 36 difiers from the back-form section 38 in that ithas a cut-out portion 63 which defines the interruptions in the steps54, 55, 56, 57 and 58 and accommodates the snap-out winding form portion38. The mid-form section 36 is also formed with an axially extendingopening 64 (see FIG. 10) to accommodate the movement of the stripper 24and stripper actuating shaft 60.

As is best seen in FIG. 5, a trip plate 65 is located at the top of themid-form section 36, and as the mid-form section 36 is lowered, itsuccessively engages the four latch pawls 67, 68, 69 and 70 (see FIGS. 6and 7) to release the snap-out winding form plates 40, 41, 42 and 43.The first snap-out winding form plate 39 does not have a latch pawlrelease but is spring-biased into position when the jump tube 51positions the first turngauging step 54 in the path of the wire 62.

Referring more specifically to FIGS. 5 through 9, I will nowspecifically describe the various parts of the snap-out form portion 38of the non-collapsible coil tum-forming assembly 21. It will beappreciated that the snap-out form portion 38 does not move with thejump plate 50. The snap-out form portion 38 includes a housing 72 andthe five snap-out winding form plates 39, 40, 41, 42 and 43. As will beseen in FIG. 9, the snap-out winding form plate 43 has a pair of spacedpins 73 and 74 that engage mating holes 75 and 76 formed on the top ofcurved blade 34 of the coil injection tooling 20. It will be seen thatthe snap-out winding plate 43 has a fill-in form section 77. When thecoil tum-forming assembly 21 has been located or jumped to the positionwhere tum-gauging step 54 is in the path of the wire 62 being wound,winding plate 43 is released from its latched position and will beextended by the associated springs 48 to place the fill-in form section77 in the interruption of the mid-form 36 and in the path of the wire62.

When the pins 73, 74 are engaged with the blade 34, the curved surface78 on the fill-in form section 77 mates with the adjacent curved surface79 of the blade 34 to provide a smooth passage for the entry of wire 62into the coil injection tooling 20. Thus the snap-out form plates, andparticularly their fill-in form portions, provide guides or guide meansfor leading the generated turns into the coil injection tooling.

.As is seen in FIG. 7, the pawls 67, 68 are latched in the openings 80,81 formed in the snap-out winding form housing 72. The other two pawls69, 70 are on the back side of the housing 72 and cannot be seen in theview of FIG. 7. The four pawls 69, 67, 70 and 68 are positioned atpreselected vertical brought into the path of the wire being wound. Eachset of a tum-gauging step and snap-out winding fomi plate, particularlythe fill-in form section, provide a form for generating the turn of wirefor a particular coil.

It will be seen in FIG. 7 that the snap-out winding form plates 39, 40,41, 42 and 43 are formed with lugs 82, 83, 84, 85 and 86. When themidand back-form sections 36, 37 of the coil form assembly 21 arereturned to their initial positions after the coils for a coil group aredeveloped, the lugs 82, 83, 84, 85 and 86 are engaged by the trip plate65, and the snapout winding form plates 39, 40, 41, 42 and 43 arereturned to their retracted positions. The snap-out winding form plate39 is held in its retracted position by trip plate 65 while winding formplates 40, 41, 42 and 43 are latched in their retracted positions byengagement of latch pawls 69, 67, 70 and 68 with housing 72. It will beappreciated that the snap-out portion housing 72 is bolted to the drivecontrol housing 87.

In FIG. 8 I have shown a fragmentary sectional view of the trip plate43, the jump plate 50, the mid-form section 36, the trip plate 65, andsnap-out housing 72 to illustrate the interrelationships of these parts.It will be seen that the latch pawl 68 is pivotally supported on a pin88 and is biased outwardly into engagement with the opening 81 of thesnap-out portion housing 72 by a spring 89 when the snap-out plate 43 isin the latched position. When the mid-form section 36 is lowered, tripplate 65 engages the latch pawl 68 to force its lower edge 680 out ofengagement in the opening 81 of the snap-out portion housing 72 therebyunlatching the snap-out winding form plate 43. The winding form plate 43then is extended by springs 48 until latch pawl arm 68b engages the edgeof opening 81. When the mid-form section 36 is returned to its initialposition upon the completion of the winding of the coils of a coilgroup, the trip plate 65 will engage the lugs 86 to return the snap-outplate 43 to its latched position.

In a similar manner the snap-out plates 40, 41 and 42 are unlatched whenthe trip plate is lowered sufficiently to engage latch pawls 69, 67 and70. As the mid-form section is returned to its initial position, thetrip plate 65 will engage the lugs 83, 84 and 85 to raise the snap-outplates 40, 41 and 42 to their latched positions. The trip plate 65 alsowill engage lugs 82 to move the snap-out plate 39 from the coilinjection tooling.

Referring now to FIGS. 3 and 4, I will now more fully describe the wirecutter and holder 23. In the views illustrated therein, the flyer pathis indicated by the broken line 90. As viewed in FIGS. 3 and 4, theright-hand portion of the wire 62 extends to the flyer 23, while theleft-hand portion of the wire 62 is either a termination portion orextends to the last previously developed coil.

The function of the wire cutter and holder 23 is to hold and cut thewire 62 at preselected points in the winding cycle. The wire cutter andholder 23 includes a support bracket 91, a

hook arm 92 pivotally supported by a pin 93 attached to the bracket 91.At one end the hook arm 92 is formed with a hook 94 for engaging thewire 62. The hook 94 includes a cutting edge 95 and when engaged in thecutting block 96 as illustrated in FIG. 3, cutting edge 95 will shearthe wire 62. The hook arm 92 is connected at its other end to a clevis97 attached to the rod 98 of a double-acting pneumatic cylinder 99.

In order to permit adjustments to be made in the holding pressureapplied to the wire 62, an adjusting screw 100 is provided. Theadjusting screw 100 is supported over the hook arm 92 by means of aplate 101 attached to the bracket 91.

From the above description of the winding head 19, the flyer 22, andwire cutter and holder 23, it will be apparent that certain controlfunctions must be carried out to effect the jumps or movements of thejump form portion 35 in proper sequence, to drive the flyer 22, tooperate the wire cutter and holder 23, and to actuate the stripper 24upon completion of a winding operation. A winding control and drive thatis suitable for this purpose is described in application, Ser. No.826,744 filed on Apr. 2, 1969; which is a continuation-in-partapplication of application, Ser. No. 594,462 filed on Nov. 15, 1966; andwhich is assigned to the same assignee as the present invention.

Having more specific reference now to FIGS. 5, 6, 11 and 12, I will nowmore fully explain and describe the control and drive for the windinghead 19. The stepped vertical movement is imparted to the winding head19 by the jump tube 51 attached to the jump plate 50. A pair ofvertically extending guide rods 102 prevent any rotational movement ofthe coil form assembly 21. The winding flyer 22 is driven by a spindle103 which is supported for rotation within the drive and control housing87 by means of the ball bearings 104 and 105.

It will be seen in the schematic diagram shown in FIG. 11 that the jumptube 51 and the stripper actuating shaft 60 extend through the flyerspindle 103. The stripper actuating shaft 60 is biased in the upwardposition as shown by a spring 600. Near the top end of the jump tube 51and inner race 106 of a ball bearing 107 (see FIG. 12) is secured to thejump tube 51, and the outer race 108 of the ball bearing 107 is attachedto an inner sleeve 109. The cap screws 110 connect an outer sleeve 111with the inner sleeve 109 for rotation with spindle 103. Each cap screw110 has a shank portion 112 engaged in longitudinally extending slots 113 formed in the flyer spindle 103. It will be noted that the inner race114 of a second ball bearing 1 15 is attached to the outer sleeve 1 1 1.The outer race 1 16 is secured to a jump push or yoke plate 1 17 by anannular retainer 1 18. With this arrangement it will be appreciated thatthe jump push or yoke plate 117 can effectively impart a longitudinalmovement to the jump tube 51 while the spindle 103 rotates around it. Inthis illustrative embodiment of my invention, the winding flyer spindle103 is driven by an electric motor 120 in a one-to-one speed ratiothrough a pulley system. The pulley system includes pulleys 121, 122,123 and 124 and belts 125, 126.

The motor 120 is connected to a tape reader 127 by means of the leads128 and 129. Pulley 122 driven by the motor 120 drives a control shaft130 which rotates a transparent disc 131 and an eccentric arm 132.Light-impervious mark 133, 134 on the disc 131 interrupt the light fromphotoelectric cells 135, 136 to provide signals to tape reader 127indicative of the position of the flyer and the number of revolutionstraversed by the flyer. Leads 137 and 138 connect the photoelectriccells and 136 in circuit with the tape reader 127.

It will be noted that the yoke plate 117 is attached to a cylindricalguide member 139 slidably disposed along the rod 140 for limiting themovement of the yoke plate 1 17 from an upper position where it buttsagainst the support bracket 141 and a lower position where it restsagainst the shoulder 142. The stepped movement of the jump tube 51 iscontrolled by a series of four trip bars 143, 144, 145 and 146. Adouble-acting air cylinder 147 having a rod 148 attached to the yokeplate 117 normally during winding biases the yoke plate 117 in adownward direction. The trip bars 143, 144, 145 and 146 are pivotallysupported on a bracket 149 and are normally held in a hold position forengagement with the yoke plate extension 150 by springs 151, 152, 153and 154. The trip bars 143, 144, 145 and 146 are moved out of the holdposition by means of an oscillating mechanism 155 having four pins 156,157, 158 and 159 which are movably carried in a rocker arm 160 driven bythe eccentric arm 132. Bell cranks 161, 162, 163 and 164 operativelyconnected to solenoids 165, 166, 167 and 168 move a pin under itsassociated trip bar whenever a solenoid is energized. The solenoids 165,166, 167 and 168 are connected with the tape reader 127 by means of theelectric leads 169, 170, 171 and 172. When a pin is extended and engagesa trip bar, the trip bar will pivot out of the stop position, and theyoke plate 117 will jump or move into engagement with the next trip bar.It will be appreciated that so long as the pins 156, 157, 158 and 159remain in their retracted positions, the oscillatory movement of theeccentric arm 132 does not have any effect on the trip bars, since thepins make no contact with the bars.

In order to insure that all the turns have been moved off thetum-generating forms upon completion of the tum-generating operation,the stripper 24 is actuated by an air cylinder 174. A rod 175 of the aircylinder 174 is actuated in response to a signal from the tape reader127 and strikes a strike plate 176 attached to the stripper shaft 60 andmoves the stripper 24 downwardly. As the stripper 24 moves in thedownward direction, the spring 105 is compressed, and the strike plate176 and stripper 24 are returned to their initial positions by means ofthe spring 105 when the coil turn stripping operation is completed.

In FIG. 13 l have illustrated a coil developing apparatus 18 as appliedto a turntable 177 with the winding and coil injecting stations beingshown. After the first coil group is developed, the coil injectiontooling is rotated 180 degrees by the gears 187, 188 (see FIG. 1) toplace the other set of turn receiving slots under the snap-out plates39, 40, 41, 42 and 43. When the second coil group is developed by theapparatus 18, the turntable 177 is indexed to place the coil injectiontooling with the two coil groups in position at the coil injectionstation while the other coil injection tooling is moved over to thewinding station.

The coil injection tooling 20 is illustrated with the longitudinal axesof the curved blades 30-34 disposed generally vertically and with thecoil tum-forming assembly 21 positioned above the coil injectiontooling. Such an arrangement is not necessary and other dispositions ofthese parts can be utilized. It will be realized that, to obtain anysubstantial assistance from the force of gravity in moving generatedturns into the turn receiving slots, the coil accommodating deviceshould be positioned, at the coil developing station, with thelongitudinal axes of the curved blades nonhorizontal and with the distalends of the blades positioned generally upward.

At the coil injecting station, a core clamping and positioning assembly,generally identified by reference numeral 178, is provided. The coreclamping and positioning assembly 178 includes a main vertical frame179, a clamping arm 180, a double-acting cylinder 181 having a rod 182attached to a cylinder cam 183. As will be seen in FIG. 13 therectilinear motion of the rod 182 is converted by the cylinder cam 183on which the clamping am 180 is supported to requisite vertical andhorizontal movements necessary to lift a stator 184 clamped in theclamping am 180 from juxtaposition to coil injection tooling 20 and toswing the arm 180 angularly away from the turntable 177, when the arm180 is axially removed from the coil injection tooling, where the stator184 can be conveniently removed by an operator.

Having more specific reference now to FIGS. 1, 2, 5, l1 and 13, I willnow more fully describe a cycle of operation of the improved coildeveloping apparatus 18.

When the coil injection tooling 20 is located in position under the coiltum-forming assembly 21, the jump cylinder 147 positions the push plate117 so that the extension 150 butts against the first trip bar 143. Thiscauses the first snapout winding form plate 39 to be engaged by springpressure against the first curved blade 30 of the coil injection tooling20 and the first turn-gauging step 58 to be positioned in the path ofthe wire 62. The flyer 22 now starts rotating to generate turns of wireon the first turn-gauging step 54, including the fill-in form portion ofwinding fonn plate 39. After approximately three turns are generated,the start end of the wire 62 can be released from the wire cutter andholder 23. The number of turns generated about the first turn-gaugingstep 54 of the coil tum-forming assembly 21 is determined by the punchedtape of the tapevreader 127. As the turns of wire are generated aroundthe turn-gauging step 54, including the snap-out winding form plate 39,they tend to slide downwardly (as seen in FIG. 1) and enter the turnreceiving slot 25. The first coil is actually formed in the turnreceiving slot 25.

With the turn count for the first coil completed, the pin 156 isextended by solenoid to cause the push plate 117 to engage the secondtrip bar 144. The second snap-out winding form plate 40 is nowunlatched, and the second turn-gauging step 55 is in the path of thewire 62. The second snap-out winding plate 40 is held against the curvedblade 31 of the coil injection tooling 20 by spring pressure. Also, thepair of pins at the end of the second snap-out winding form plate 40 areengaged in the mating holes in the curved blade 31 to maintain thesecond snap-out winding form plate 40 rigidly in alignment therewith.When the predetermined number of turns have been generated to completethe second coil in coil receiving slot 26 of the coil injection tooling20, solenoid 166 is energized by the tape reader to cause trip pin 157to be extended. The extension 150 of the push plate 117 engages thethird trip bar thereby causing the jump form portion 35 to be loweredand unlatch the third snap-out winding form plate 41.

Similarly, after a predetermined number of turns have been generated tocomplete the winding of the third coil, solenoid 167 is energized by thetape reader 127 to cause the extension of push plate 117 to engage thefourth trip bar 146. The turn-gauging step 57 with the fourth snap-outwinding form plate 42 is now in the path of the turns generated from thewire 62, and the turns for fourth coil of the coil group are generated.

Upon completion of the fourth coil, solenoid 168 is energized by thetape reader 127 to effect the fifth jump and place the fifthturn-gauging step 58 and its associated snap-out winding form plate 43in the path of the wire 62 being wound by the flyer 22 thereby togenerate the turns for the fifth and last coil of the coil group. Itwill be appreciated that as the flyer 22 rotates around a tum gaugingstep, the wire 62 is laid on the bevel 61 of a turn-gauging step. Thus,each turn of wire as it is placed on the winding form by the flyerpushes the preceding turns into the coil receiving slots of theinsertion tooling 20. Also with the nonhorizontal positioning, gravityassists in moving the turns into the slots 25-29.

Thus, snap-out winding form plates 40, 41, 42 and 43 are successivelyunlatched as the jump form portion 35 is lowered to place theprogressively larger turn-gauging steps 55, 56, 57 and 58 in the path ofthe wire 62. In the exemplification of the invention, the tape reader127 not only controls the turn count of the coils being developed butalso preferably controls the number of the slow down turns included atthe end of the total turn count for the fifth coil. It will beappreciated that a slow down of the flyer speed is required in order toallow the wire cutter and holder 23 to be brought into the wire pathduring the last turn and also to permit control of the wire location. Asignal indicating the rotational position of the flyer head is providedby means of the tape mark 134 on the translucent disc 131. Also, at theend of the total turn count of the fifth coil, the wire stripper 24 isactuated by the stripper air cylinder 174 and not only clears the coiltum-forming assembly 21 of any turns that may not have moved off butalso pushes the turns into the coil turn receiving openings of the coilinjection tooling 20 sufficiently so that they will not spring out.

After the first group'of coils have been developed in the tooling (thefirst group of coils being the first pole of a two pole stator in thisexemplification of the invention), the snapout winding form plates 39,40, 41, 42 and 43 are returned to their retracted positions. The coilinjection tooling 20 is then indexed into position by rotating it 180 toreceive the turns for the coils of the second pole. The turns for thecoils of the second pole are generated in essentially the same sequenceas the coils of the first coil group and are received in appropriateslots in the coil injection tooling to develop the coils. When the coilsof the second coil group are wound and the coil tumforming assembly 21and the stripper 24 moved to their initial positions, the coil injectiontooling, containing the two coil groups is moved to an injectionstation, as shown in FIG. 13, where the coil groups are axially insertedinto the slots of the stator 184.

From the foregoing description it will be apparent that the snap-outwinding form plates cooperate with the curved blades of the coilinjection tooling to guide or effect a transfer of the turns for eachcoil as they are being generated directly into the coil injectiontooling. This provides the important advantage that the coils can now bedirectly inserted into a stator core of an electric motor using only onecoil form assembly and one coil injection tooling. In collapsible arbor.type machines it has been proposed that a collapsible arbor be providedfor each coil group, thus for four pole stators, four arbors are needed.Further, unnecessarily long interpole wire lengths result. Anotheradvantage of the improved snap-out winding form arrangement is that thecoil injection tooling does not have to be lowered or raised intoposition to receive the turns from the winding apparatus and theover-all size is not that large. In collapsible arbor types of machineseach of the turn-gauging steps must be sufficiently large-toaccomtl'lodate all of the turns of a coil of maximum size. It ispossible to use the apparatus of the present invention where the coilinjcction tools are mounted on a conveyor, whether a rotary indexingtable or an in-line type of arrangement, and it will be apparent alsothat the snap-out winding form arrangement is readily adapted tosemi-automated type of production. Further, the coil developingapparatus is capable of winding a .wide range of diameter wire sizes.Apparatus was constructed in accordance with the embodiment of theinvention illustrated in FIGS. 1-13, which was capable of developingcoils in coil injection tools, the wires having a diameter size rangingfrom 0.0 l to 0.0508 of an inch without need for changing the openingsin the tools. Further, unlike prior art devices, there is littletendency for the turns to become jammed or crossedover as the turns arebeing deposited into the tools, thereby reducing if not entirelyeliminating potential interference with a subsequent smooth transfer ofthe turns from the tools into selected slots of a magnetic core. Otherbenefits result from a short period of time employed for the combineddeveloping and injecting operations permitted by the present invention,the lack of need for collapsible winding arbors, which correspond innumber to the magnetic poles of the core, and the usual relatedinherently expensive components, and the high level of productionefficiency attainable using the present inyention.

Although in the illustrated exemplification of my invention, I haveshown a coil injection tooling for accommodating the coil groups of atwo pole stator, it will be appreciated that the improved coildeveloping apparatus is readily adapted for developing windings formagnetic cores having in excess of two poles. For instance, when a coildeveloping apparatus is used to wind four coil groups into coilinjection tooling, the tooling is sequentially rotated or turned threetimes through 90 to locate the tool at the proper position for receivingthe turns of the coil groups. In addition, although a latchingarrangement for releasing five snap-out winding form plates wasillustrated, it will be understood that, depending upon the number ofcoils to be wound, more or less than five snap-out winding form platesmay be employed in the practice of one form of the invention.

Further, if desired the individual wire turn lengths in a given coil maybe readily varied merely by gradually or progressively changing thedistance between winding forms in the non-collapsible form assembly asthe turns are being developed into coils in the tool. For instance,back-form 37 may be mounted to be moved gradually toward or away frommid-form 36 by a screw feed or the like. Thus, by regulating movementand direction of the feed, the turns may be progressively shortened,lengthened or both in the same coil, as dictated by the slotconfiguration of the magnetic core during coil development in the toolsor other slotted coil group accommodating member.

Referring now to FIGS. 14 and 15 in particular, there is illustratedcertain details of a coil tum-forming assembly which is basicallysimilar to the coil tum-forming assembly 21, of FIGS. 1-13, but has beenmodified somewhat in order to selectively vary the length of turns beinggenerated for a predetermined coil or coils. The snap-out form portion38 is the same, and the mid-form section 36 of the jump form portion isthe same; however, the back-form section 191 has been modified. A rack192 is attached to the back-form section 191 by some suitable means suchas small bolts 193, and the rack is received in a slot 194 in the jumpplate 50. A pinion gear 195 is supported on the jump plate 50 by meansof a bearing structure 196 and has teeth meshing with the teeth of therack 192. Thus, as the pinion gear 195 is rotated in oppositedirections, it will move the rack to the right or the left (as seen inFIGS. 14 and 15) and the rack will carry the back-form section 191 withit.

In order to selectively rotate the pinion gear, and thus move theback-form section, a shaft 197 is provided with its upper end mounted inthe drive control housing 87 by a bearing structure 198. The lower end199 of the shaft is received in a slot 200 in the back-form section andincludes a longitudinally extending keyway 201. The keyway cooperateswith an elongated key 202 formed in the bearing 196 so that as the shaftrotates the bearing 196, and thus pinion gear 195, will be rotated. Thejump tube 51 can move the coil turn-forming assembly 190 longitudinally(up and down in FIGS. 14 and 15) without moving the shaft 197longitudinally as the key 202 and keyway 201 are relatively movable intheir axial direction. Within the drive control support structure 203,the shaft is connected to a warm gear 204 and the warm gear in turn isconnected to the drive shaft 205 of a small electrical motor 206.The'motor is mounted to a stationary portion of the support structure203.

In order to provide electrical energy to the motor, the flyer mechanism22 includes a rotary sleeve 207 having a first set of slip rings 208provided on its outer surface and a second set 209 provided on its innersurface, these slip rings being electrically interconnected through thesleeve. A pair of brushes 210 are mounted in engagement with the outerslip rings 208 and may be connected to a suitable source of electricalenergy while a second set of brushes 211 are connected to the inner sliprings 209 and are also connected to the motor 206. Thus at appropriateand predetermined times the motor 206 may be energized to rotate theshaft 197 and thus the pinion gear 195. This rotary motion of the piniongear is translated to rectilinear motion of the rack 192 which carrieswith it the back-form section 191.

As the back-form section 191 moves to the right or left (as seen inFIGS. 14 and 15), the distance between its tum-gauging steps 54-58 andthe corresponding snap-out winding form plates 39-43 is varied. Thiseffectively varies the circumference of the form about which the turnsof wire are being generated and thereby selectively varies the length ofsuccessive turns. Since the shaft 197 may be rotated independently ofthe remaining portion of the tum-forming assembly 190, the spacing maybe varied during a tum-generating operation and thus vary the length ofsuccessive turns generated for an individual coil. Motor 206 also may beutilized to move backform section 191 before a tum-generating operationbegins so as to set difierent coil lengths for the turns of successivelygenerated coil groups.

It will be realized that when the back-form section 191 is moved to theleft (as seen in FIGS. 14 and 15) during turn generation to increase thelength of successively wound turns, care must be taken both as to thespeed which the back-form section is moved and the pitch of thetum-gauging steps to insure that previously generated turns will moveoff of the tumgenerating assembly into associated turn receiving slotsof the injection tooling and will not bind on the tum-gauging steps.

While the invention has been explained by describing various embodimentsthereof, it will be apparent that many modifications may be made withoutdeparting from the spirit of the invention. It is therefore intended tocover all such equivalent variations as come within the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. Apparatus for developing at least one coil of electrically conductivewire for use in a magnetic core, said apparatus comprising: a coiltum-forming assembly including a jump form portion and a snap-out formportion, said jump form portion having a plurality of turn-gaugingsteps, each of said tumgauging steps having an interruption formed atone side thereof; said snap-out form portion having a plurality ofsnapout winding form plates supported adjacent to the interruptions ofsaid tum-gauging steps; each of said snap-out winding fonn plates havinga fill-in fonn section for spanning a corresponding one of saidinterruptions; flyer means for generating turns of wire about said coilturn-forming assembly; jump means for locating a predetermined one ofthe tum-gauging steps in the path of the turns being generated; andmeans for concurrently extending a corresponding one of said snap-outwinding form plates to place a corresponding one of said fill-in formsections in alignment with the interruption of said one tum-gaugingstep; said one tum-gauging step and said one fillin form sectioncooperating to provide a form for generating the turns of the at leastone coil.

2. The apparatus as set forth in claim 1 wherein said snapout formportion includes a generally cylindrically shaped housing; said snap-outplates being slidably disposed in said housing; at least one of saidsnap-out winding form plates being spring-biased to an extended positionand latched in a retracted position; and said jump form portion includesmeans for releasing a latched snap-out winding form plate as said jumpmeans locates a corresponding turn-gauging step in the path of the turnsof wire being generated.

3. The apparatus as set forth in claim 1 wherein said jump form portionis movable relative to said snap-out form portion and said apparatusincludes means for moving said jump form portion relative to saidsnap-out form portion during turn generation for varying the relativesize of successively generated turns.

4. Apparatus for developing at least one coil of conductive wire for usein a magnetic core, said apparatus comprising: a coil tum-formingassembly including a jump form portion and a snap-out form portion; saidjump fonn portion having a plurality of tum-gauging steps, each of saidtum-gauging steps having an interruption formed at one side thereof;said snapout form portion having a plurality of guide means, each ofsaid guide means being positioned for effectively spanning theinterruption of a corresponding tum-gauging step; flyer means forgenerating turns of wire about said coil tum-forming assembly, jumpmeans for locating a predetermined tum-gauging step in the path of thewire generating the turns; and trip means for concurrently positioning acorresponding guide means in alignment with the interruption of saidpredetermined tum-gauging step; said predetermined tum-gauging step andsaid corresponding guide means cooperating to provide a form forgenerating the turns of the at least one coil.

5. The apparatus as set forth in claim 4 further including means forproviding relative motion between at least part of said jump formportion and said snap-out form portion during generation of the turns ofwire for selectively varying the lertfths of the turns of the at leastone coil.

. The apparatus as set forth in claim 4 including control means foractuating said jump means to successively place other predeterminedtum-gauging steps in the path of the wire generating the turnssubsequent to the completion of the turns of wire for each coil; saidtrip means concurrently positioning successive corresponding guide meansin alignment with the interruption of each such tum-gauging step; saidsuccessively placed tum-gauging steps and said corresponding guide meanscooperating to provide forms for successively generating turns of aplurality of coils.

7. Apparatus for developing at least one coil of electrically conductivewire for use in a magnetic core, said apparatus comprising: a coiltum-forming assembly including first and second portions movablerelative to one another; winding means; said coil turn-forming assemblyand said winding means being relatively movable for generating turns ofwire about said coil tum-forming assembly; drive means for effectingrelative movement between said first and second portions of said coiltum-forming assembly during turn generation for varying the relativesize of successively generated turns.

8. Apparatus as set forth in claim 7, wherein: each of said first andsecond portions of said coil tum-forming assembly includes a pluralityof turn-gauging steps selectably alignable with corresponding steps ofthe other of said first and second portions to provide selectable formsfor generating turns of different selected coils and said drive meanseffects relative movement between said first and second portions duringturn generation for a selected coil to vary the relative size ofsuccessively generated turns of the selected coil.

9. Apparatus for developing selected coils of conductive wire for use ina magnetic core, said apparatus comprising: a coil tum-forming assemblyincluding first and second portions; said first portion having aplurality of tum-gauging steps, each of said turn-gauging steps havingan interruption; said second portion having a plurality of guides; meansfor selectively positioning predetermined ones of said guides in theinterruptions of corresponding tum-gauging steps to provide selectableforms; winding means; said coil turn-forming assembly and said windingmeans being relatively movable with said winding means aligned withselected forms for generating turns of wire for selected coils.

10. Apparatus as set forth in claim 9, further including drive means foreffecting movement of said first portion relative to said second portionduring turn generation for varying the relative size of successivelygenerated turns of a selected coil.

1. Apparatus for developing at least one coil of electrically conductivewire for use in a magnetic core, said apparatus comprising: a coilturn-forming assembly including a jump form portion and a snap-out formportion, said jump form portion having a plurality of turn-gaugingsteps, each of said turngauging steps having an interruption formed atone side thereof; said snap-out form portion having a plurality ofsnap-out winding form plates supported adjacent to the interruptions ofsaid turngauging steps; each of said snap-out winding form plates havinga fill-in form section for spanning a corresponding one of saidinterruptions; flyer means for generating turns of wire about said coilturn-forming assembly; jump means for locating a predetermined one ofthe turn-gauging steps in the path of the turns being generated; andmeans for concurrently extending a corresponding one of said snap-outwinding form plates to place a corresponding one of said fill-in formsections in alignment with the interruption of said one turn-gaugingstep; said one turngauging step and said one fill-in form sectioncooperating to provide a form for generating the turns of the at leastone coil.
 2. The apparatus as set forth in claim 1 wherein said snap-outform portion includes a generally cylindrically shaped housing; saidsnap-out plates being slidably disposed in said housing; at least one ofsaid snap-out winding form plates being spring-biased to an extendedposition and latched in a retracted position; and said jump form portionincludes means for releasing a latched snap-out winding form plate assaid jump means locates a corresponding turn-gauging step in the path ofthe turns of wire being generated.
 3. The apparatus as set forth inclaim 1 wherein said jump form portion is movable relative to saidsnap-out form portion and said apparatus includes means for moving saidjump form portion relative to said snap-out form portion during turngeneration for varying the relative size of successively generatedturns.
 4. Apparatus for developing at least one coil of conductive wirefor use in a magnetic core, said apparatus comprising: a coilturn-forming assembly including a jump form portion and a snap-out formportion; said jump form portion having a plurality of turn-gaugingsteps, each of said turn-gauging steps having an interruption formed atone side thereof; said snap-out form portion having a plurality of guidemeans, each of said guide means being positioned for effectivelyspanning the interruption of a corresponding turn-gauging step; flyermeans for generating turns of wire about said coil turn-formingassembly, jump means for locating a predetermined turn-gauging step inthe path of the wire generating the turns; and trip means forconcurrently positioning a corresponding guide means in alignment withthe interruption of said predetermined turn-gauging step; saidpredetermined turn-gauging step and said corresponding guide meanscooperating to provide a form for generating the turns of the at leastone coil.
 5. The apparatus as set forth in claim 4 further includingmeans for providing relative motion between at least part of said jumpform portion and said snap-out form portion during generation of theturns of wire for selectively varying the lengths of the turns of the atleast one coil.
 6. The apparatus as set forth in claim 4 includingcontrol means for actuating said jump means to successively place otherpredetermined turn-gauging steps in the path of the wire generating theturns subsequent to the completion of the turns of wire for each coil;said trip means concurrently positioning successive corresponding guidemeans in alignment with the interruption of each such turn-gauging step;said successively placed turn-gauging steps and said corresponding guidemeans cooperating to provide forms for successively generating turns ofa plurality of coils.
 7. Apparatus for developing at least one coil ofelectrically conductive wire for use in a magnetic core, said apparatuscomprising: a coil turn-forming assembly including first and secondportions movable relative to one another; winding means; said coilturn-forming assembly and said winding means being relatively movablefor generating turns of wire about said coil turn-forming assembly;drive means for effecting relative movement between said first andsecond portions of said coil turn-forming assembly during turngeneration for varying the relative size of successively generatedturns.
 8. Apparatus as set forth in claim 7, wherein: each of said firstand second portions of said coil turn-forming assembly includes aplurality of turn-gauging steps selectably alignable with correspondingsteps of the other of said first and second portions to provideselectable forms for generating turns of different selected coils andsaid drive means effects relative movement between said first and secondportions during turn generation for a selected coil to vary the relativesize of successively generated turns of the selected coil.
 9. Apparatusfor developing selected coils of conductive wire for use in a mAgneticcore, said apparatus comprising: a coil turn-forming assembly includingfirst and second portions; said first portion having a plurality ofturn-gauging steps, each of said turn-gauging steps having aninterruption; said second portion having a plurality of guides; meansfor selectively positioning predetermined ones of said guides in theinterruptions of corresponding turn-gauging steps to provide selectableforms; winding means; said coil turn-forming assembly and said windingmeans being relatively movable with said winding means aligned withselected forms for generating turns of wire for selected coils. 10.Apparatus as set forth in claim 9, further including drive means foreffecting movement of said first portion relative to said second portionduring turn generation for varying the relative size of successivelygenerated turns of a selected coil.